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IEEE DESIGN TEST REPORT

Report No. EU1588-H-00.1 Type EVP Station Class

Surge Arrester

This report records the results of the design tests made on Type EVP Station Class surge arresters in accordance with IEEE Standard C62.11-2012 “IEEE Standard for Metal Oxide Surge Arresters for AC Power Circuits (> 1kV)”. To the best of our knowledge and within the usual limits of testing practices, tests performed on the Type EVP arresters demonstrate full compliance with the relevant clauses of the referenced standard.

Dennis Lenk Saroni Brahma Principal Engineer Design Engineer

Date: 1/10/14

Separate reports provide details of the tests, according to the following table:

Report No. Description Clause Issue Date EU1588-H-01.1 Insulation Withstand 8.1 1/10/14 EU1588-H-02.1 Discharge Voltage 8.2 1/10/14 EU1588-H-03.1 MOV Disc Accelerated Aging 8.5 1/10/14 EU1588-H-04.1 Polymer Accelerated Aging 8.6 1/10/14 EU1588-H-05.1 Contamination 8.8 1/10/14 EU1588-H-06.1 Internal Ionization and RIV 8.10 1/10/14 EU1588-H-07.1 Partial Discharge 8.11 1/10/14 EU1588-H-08.0 Switching Surge Energy Rating 8.14 1/10/14 EU1588-H-09.0 Single-Impulse Withstand Rating 8.15 1/10/14 EU1588-H-10.1 Duty Cycle 8.16 1/10/14 EU1588-H-11.1 Temporary Overvoltage 8.17 1/10/14 EU1588-H-12.1 Short Circuit Pressure Relief 8.18 1/10/14 EU1588-H-13.1 Maximum Design Cantilever Load 8.22 1/10/14 EU1588-H-14.1 Thermal Equivalency Test 7.2.2 1/10/14

IEEE Design Test Report

Report No. EU1588-H-01.1 Type EVP Station Class Arrester

Insulation Withstand

This report summarizes the results of design tests made on the Type EVP Station Class arrester design. Tests were performed in accordance with procedures of IEEE Std C62.11-2012, “IEEE Standard for Metal-Oxide Surge Arresters for AC Power Circuits (> 1 kV).” To the best of our knowledge and within the usual limits of testing practice, tests performed on these arresters demonstrate compliance with the relevant clauses of the referenced standard.


Date: 1/10/2014

EU 1588-H-01.1 2

Type EVP Station Class Surge Arrester Insulation Withstand

INTRODUCTION: The following table lists the Type EVP arresters’ minimum strike distance, 1.2/50 required and actual impulse withstand levels, and 60 HZ required and actual wet withstand levels as defined in Sections 8.1.2.4 of IEEE C62.11-2012 standard. CONCLUSION: All housings meet or exceed these levels of voltage.

Lightning Lightning 60 HZ 60 HZ Strike Imp w/s Imp w/s Wet w/s Wet w/s

Arrester Distance Req’d Actual Req’d Actual MCOV (in) (KVc) (KVc) (kVrms) (kVrms) 2.55 6.9 12 101 5 50 5.1 6.9 23 101 10 50

7.65 8.7 35 127 15 63 8.4 8.7 38 127 16 63

10.2 8.7 47 127 20 63 12.7 10.5 58 153 25 75 15.3 10.5 70 153 30 75 17 14.2 78 207 33 101

19.5 14.2 89 207 38 101 22 14.2 100 207 43 101

24.4 14.2 111 207 47 101 29 17.9 133 261 56 125

31.5 17.9 144 261 61 125 36.5 21.5 166 313 71 148 39 21.5 178 313 75 148 42 21.5 201 313 85 148 48 25.2 221 367 94 172 57 28.9 266 421 113 194 70 43.3 333 631 141 275 74 43.3 338 631 143 275 76 43.3 356 631 151 275 84 43.3 401 631 170 275 88 43.3 401 631 170 275 98 44.7 447 652 197 283

106 44.7 487 652 215 283 115 52 532 758 235 320 131 63.5 621 926 274 372 140 69 639 1006 282 395 144 69 664 1006 293 395 152 69 709 1006 313 395 180 80 842 1166 371 436



Discharge Voltage



Date: 1/10/2014

EU 1588-H-02.1 2

IEEE Design Test Report Discharge Voltage Characteristic

TESTS PERFORMED: Residual voltage measurements were made on three single resistor elements. Tests were conducted in accordance with clause 8.3 of the IEEE C62.11-2012 standard, to determine steep current impulse residual voltages at 10 kA, lightning impulse residual voltages at 1.5 kA, 3 kA, 5 kA, 10 kA and 20 kA, and switching impulse residual voltages at 0.5 kA and 1 kA. Oscillograms of current and voltage were obtained for each test. For each test sample, all measured voltages have been rationalized to the lightning impulse residual voltage of that sample at nominal discharge current (10 kA 8/20), and the results have been displayed in graphical form. RESULTS: Tables 1, 2 and 3 show the residual voltages measured on test samples 1, 2 and 3, respectively. For each test sample, the measured residual voltages have been expressed in per unit of the lightning impulse residual voltage at nominal discharge current (10 kA, 8/20).

Table 1: Measurements made on test sample 1

Test Wave

Current Magnitude

Wave-shape Residual Voltage Oscillogram

kA μs kV p.u. Number Steep front 10 1/2 14.583 1.09 34

1.5 8/20 11.32 0.846 1 8/20 3 8/20 11.903 0.889 4

Impulse 5 8/20 12.471 0.932 7 10 8/20 13.385 1 10 20 8/20 14.452 1.08 13

Switching Impulse

0.5 43/91 10.651 0.796 22 1 40/86 11.05 0.826 25

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Test Wave

Current Magnitude



1.5 8/20 11.304 0.845 2 8/20 3 8/20 11.899 0.889 5

Impulse 5 8/20 12.465 0.932 8 10 8/20 13.38 1 11 20 8/20 14.436 1.079 14

Switching Impulse

0.5 43/91 10.651 0.796 23 1 40/86 11.05 0.826 26


Test Wave

Current Magnitude



1.5 8/20 11.338 0.846 3 8/20 3 8/20 11.902 0.888 6

Impulse 5 8/20 12.479 0.932 9 10 8/20 13.396 1 12 20 8/20 14.478 1.081 15

Switching Impulse

0.5 43/91 10.651 0.795 24 1 40/86 11.029 0.823 27

The results of the discharge voltage testing are shown graphically in the following chart.

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0.700

0.750

0.800

0.850

0.900

0.950

1.000

1.050

1.100

1.150

0 2 4 6 8 10 12 14 16 18 20

Current- kA

Dis

char

ge V

olta

ge-P

U ti

mes

10

kA 8

/20

Series1

8/20 discharge characteristic

.5 microsecond data point

Switching Surge characteristic

The values shown in this chart are all normalized to the lightning impulse residual voltage at nominal discharge current (10 kA). These values (Per-unit Ures-chart) are used to calculate the residual voltage characteristics (Ures-arrester) of assembled EVP series arresters. For the cases of switching impulse and lightning impulse residual voltages, the arrester residual voltages are calculated as follows:

Ures-arrester = Per-unit Ures-chart x Ures-nom Where: Ures-nom is the published maximum lightning impulse residual voltage of the arrester, as verified by routine test at time of arrester manufacture. For the case of steep current impulse residual voltage, the arrester residual voltage is calculated as follows:

Ures-arrester = Per-unit Ures-chart x Ures-nom + L’ h In / Tf

Where: L’ is the inductivity per unit length (= 1 µH/m) h is the length of the arrester (excluding the resistors since resistor inductance is already included in the test measurements) In is the nominal discharge current (= 10 kA) Tf is the front time of the steep current impulse (= 1µs)

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Oscillograms

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Sample 1, Oscillogram 1


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MOV Disc Accelerated Aging



Date: 3/27/14

EU 1588-H-03 2

Type EVP Station Class Surge Arrester

Disc Accelerated Aging INTRODUCTION: Tests were performed to measure MOV disc aging characteristics. Measured watts values are used to develop elevated voltage ratios kc and kr for use in proration of duty cycle and discharge current withstand test samples. TEST SAMPLES: Six arrester modules (three with the longest MOV disc and 3 with the shortest MOV disc) were tested.

TEST PROCEDURE: Tests were performed per section 8.5 of the IEEE C62.11-2012 standard. Samples were placed inside a 115°C ±2°C oven and energized at a voltage level greater than MCOV for 1,000 hours. TEST RESULTS: Watts loss for each sample was measured at relevant MCOV two hours after energization and at the completion of the 1000 hour test duration. The table below summarizes test data.

Accelerated aging test data

Sample No. -length Watts loss @ 2Hr-5Hr P1c (w)@ MCOV

Watts loss at 1000 Hr @

MCOV P2c (w)

Elevation Factor Kc

1-24 1.62 1.07 1 2-24 1.73 1.13 1 3-24 1.57 1.06 1 1-41 3.49 2.29 1 2-41 3.38 2.17 1 3-41 3.4 2.2 1

CONCLUSION: Each test sample demonstrated continually declining Watts loss at MCOV. Therefore, kc factors equal 1.0.



Polymer Aging



Date: 1/10/2014

EU 1588-H-04.1 2


Polymer Housing Aging INTRODUCTION: The polymer housing accelerated aging tests were performed per Section 8.7 of the IEEE C62.11-2012 standard. The purpose of this test was to verify the electrical integrity of the arrester polymer housing after being subjected to 1000 hours in a salt fog environment. SAMPLE PREPARATION: A 115 kV MCOV EVP arrester (longest electrical unit) was assembled for this test. Note: EVP was called PVN optima at the time of launch. The catalogue number in the third party test report (PSCPVN011500) is an equivalent EVP011500. TEST PROCEDURE: The 1000 hour weathering test was performed per Section 8.7.3 of the IEEE C62.11-2012 standard. TEST RESULTS: The test arrester successfully withstood the 1000 hour salt fog exposure test with no evidence of surface tracking, erosion, or puncturing. Per Section 8.7.4, the reference voltage change, as a result of the 1000 hour test, was less than the allowed 5%. In addition, the partial discharge measured at the completion of the test was less than the allowed 10pC. TEST CONCLUSIONS: The EVP Station Class arrester design successfully passed the 1000 hour salt fog test, as defined in Section 8.7 of the IEEE C62.11-2012 standard.

EU 1588-H-04.1 3

ANNEX- Salt Fog Test

The following attachment confirms the successful completion of the salt fog polymer aging test performed on the longest Type EVP electrical unit.

EU 1588-H-04.1 4



Contamination



Date: 1/10/2014

EU 1588-H-05.1 2

Type EVP Station Class Surge Arrester Contamination

INTRODUCTION: The polymer housing accelerated aging tests were performed per Section 8.8 of the IEEE C62.11-2012 standard. The tests were performed on a three unit 180 kV MCOV arrester. TEST PROCEDURE: The partial wetting contaminant was prepared per Section 8.8.2.2 and the test procedure was performed per Section 8.8.2.3 of the IEEE C62.11-2012 standard. Prior to the application of contaminant (450 ohm-cm resistivity), the arrester was energized at MCOV for 1 hour. After 1 hour of energization, the arrester was de-energized and slurry contaminant was applied over the entire surface of the bottom half of the arrester. After a 7 minute wait, the arrester was energized at MCOV for 15 minutes, at which time the voltage was turned off and the bottom half of the arrester re-sprayed with contaminant. Within 5 minutes of de-energization, the arrester was reenergized at MCOV. After 15 minutes, the arrester resistive component of current was recorded. After 30 additional minutes at MCOV, re-measurement of the resistive current confirmed thermal stability at which time the test was completed. TEST RESULTS: The 180 kV MCOV arrester demonstrated thermal stability after the second partial wetting test series. No unit or arrester flashover occurred during the above testing. Disassembly of the test arresters revealed no damage to the internal components as a result of the partial wetting contamination test.



Radio Influence Voltage



Date: 1/10/2014

EU 1588-H-06.1 2


Contamination TEST PROCEDURE AND SAMPLE: Internal ionization and RIV testing was performed per clause 8.10 of the IEEE C62.11-2012 standard. The test was performed on a 180 kV MCOV EVP arrester. TEST EQUIPMENT: Equipment and test methods conformed to NEMA LA 1-1992 requirements. Prior to the test, the Stoddart Noise Meter NM-25T was calibrated using a General Radio Signal Generator Type 1001-A. TEST RESULTS: A background noise level of 1.2 µV was measured at an open circuit voltage of 189 kV (105% MCOV). With the 180 kV arrester placed in the circuit, a noise level of 1.2 µV was measured. CONCLUSION: The 180 kV MCOV EVP arrester passed test requirements per Section 8.10 of the IEEE C62.11-2012 standard, as measured noise levels were within the 10 µV RIV test limit.



Partial Discharge



Date: 1/10/2014

EU 1588-H-07.1 2

Type EVP Station Class Surge Arrester Partial Discharge

INTRODUCTION: The polymer housing partial discharge test was performed per Section 8.11 of the IEEE C62.11-2012 standard. The test was performed on a 180 kV MCOV EVP arrester. TEST EQUIPMENT: Equipment and test methods conformed to the IEEE 454-1979 standard. TEST RESULTS: The arrester with grading ring was energized at 1.05 times MCOV. At 189 kV, the arrester’s partial discharge level measured 6.5 pC, with an ambient 5.8 pC background level. CONCLUSION: The 180 kV MCOV EVP arrester passed test requirements per Section 8.11 of the IEEE C62.11-2012 standard, as measured partial discharge levels were within the 10 pC test limit.



Switching Surge Energy Rating



Date: 1/10/2014

EU 1588-H-08 2


Switching Surge energy Rating INTRODUCTION: Switching surge energy rating tests were performed per section 8.14 of the IEEE C62.11-2012 standard. Tests were performed per Station Class arrester requirements. The main objective of this test is to claim an energy class as per Table 13 of the above mentioned standard. TEST SAMPLE: As required by the standard, the prorated test sections contained the minimum MOV mass required for the design. TEST PROCEDURE: The test sections were conditioned with six groups of three current impulses corresponding to energy class F (11kJ/kV). The assigned conditioning level testing was followed by two 65kA, 4/10 impulses, spaced 50 to 60 seconds apart. The prorated sections were then placed into an oven until the temperature stabilized at 68°C. After stabilization, test samples were subjected to long duration current impulses (2000 to 3000 µs). Within 100ms from the application of the second discharge the duty cycle rated voltage was applied for 10s followed by power frequency recovery voltage for 30mins to demonstrate thermal recovery. TEST RESULTS: MCOV = 0.795*Vref; Duty cycle rated voltage = 1.236*MCOV MCOV of Sample ≤ 9.302 kV rms (calculated from measured Vref) The targeted energy class for this design was Class F with a 2-shot energy rating of 11 kJ per kV MCOV. As such, all test sections were subjected to 18 shots having a 5.5 kJ per kV MCOV energy rating. Figure 1 shows the Class F conditioning impulse while Figure 2 shows an oscillogram of a typical 65 kA high current impulse.

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Figure 1: Conditioning impulse at class F

Figure 2: Example of 65kA (4/10) impulse waveform

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During the thermal recovery portion of the switching surge energy rating test, it was discovered that the prorated test sections could not thermally recover after exposure to the required Class F 11 kJ per kV MCOV energy discharges, followed by 10 seconds at rated voltage. The thermal recovery testing was repeated at the Class E 2-shot energy rating level of 9 kJ per kV MCOV. Figure 3 shows an oscillogram of the energy discharge followed by 10 seconds at rated voltage on sample 2, while Figure 4 demonstares the thermal stability of the test section during the recovery voltage portion of the test.

Figure 3: Class E energy shot on Sample 2 (41.859kJ/shot)

Tables 1 and 2 illustrate the duty cycle and thermal recovery data respectively.

Time (sec)

Vrated (KVc)

60Hz (mA)

0.060 16.521 161.7 1.032 16.531 158.3 2.064 16.573 154.2

3 16.594 154.2 4.008 16.594 151.3 5.016 16.583 147.5 6.048 16.583 148.8

7.08 16.583 147.9 8.136 16.563 144.6

9.10 16.573 147.1 10.20 16.594 148.3

Table 1: 10 sec Duty Cycle Voltage data on Sample 2

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Elapsed Time

Recovery (KVRMS)

It (mAC)

Ir (mAC) Watts

0:00:00 9.59 -12.53 -11.82 48.25 0:00:30 9.62 -10.57 -10.26 40.55 0:01:00 9.56 -9.02 -8.65 35.68 0:02:00 9.59 -8.56 -7.94 33.22 0:05:00 9.56 -7.04 -6.78 28.32 0:10:00 9.56 -6.28 -6.06 24.75 0:20:00 9.54 -5.17 -4.73 20.71 0:30:00 9.57 -4.87 -4.55 19.12

Table 2: 30 min Recovery Voltage data on Sample 2

Figure 4: Recovery Oscillogram- Sample 2

Per the test evaluation procedure as specified in Section 8.14.5 of the standard, the switching surge voltage of each test section was measured before and after the energy surge duty testing. Table 3 summarizes the results of this testing. Additionally, each test section showed no evidence of physical damage.

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Sample no.

1 kA IR Before(kVc)

1 kA IR After (kVc)

% Change

1 22.866 22.553 -1.37% 2 22.900 22.419 -2.10% 3 22.883 22.410 -2.06% 4 22.874 22.444 -1.88%

Table 3: 1kA IRs before and after

Conclusion: The Type EVP prorated sections successfully passed the switching surge energy requirements of Energy Class E as specified in Table 13 of IEEE C62.11-2012.



Single Impulse Withstand Rating



Date: 1/10/2014

EU 1588-H-09.0 2

Type EVP Station Class Surge Arrester Single Impulse Withstand rating test

INTRODUCTION: The single-impulse withstand rating test was performed per Section 8.15 of the IEEE C62.11-2012 standard, on ten MOV blocks. TEST PROCEDURE: Test was performed on 10 of the longest MOV blocks used in the EVP product line. The discharge voltage (10kA, 8/20) and the reference voltage (at 9.5mA) were measured before and after the long duration impulses for evaluation. Each sample was then subjected to ten groups of two long duration impulses of 2.22 ms and a charge content of 2.66 C. Figure 1 shows the long duration impulse waveform applied on each of the MOV discs.

Figure 1: Wave shape of long duration impulse wave form

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Sample No 10 kA IR Before (kVc)

10 kA IR After (kVc)

% Change

Vref @ 9.5mA Before (kVc)

Vref @ 9.5mA

After (kVc)

% Change

1 13.63 13.68 0.37% 8.39 8.56 1.98% 2 13.60 13.64 0.29% 8.39 8.55 1.84% 3 13.50 13.54 0.30% 8.32 8.46 1.68% 4 13.61 13.65 0.29% 8.39 8.54 1.76% 5 13.58 13.63 0.37% 8.34 8.51 1.95% 6 13.56 13.6 0.29% 8.36 8.52 1.84% 7 13.62 13.67 0.37% 8.40 8.56 1.86% 8 13.63 Failed - 8.38 Failed - 9 13.59 13.63 0.29% 8.37 8.55 2.12%

10 13.57 13.61 0.29% 8.36 8.54 2.14% Table 1: Before and After Discharge Voltages and Reference Voltages

Conclusion: The test was successfully completed as per the IEEE C.62.11-2012 requirements. The change in discharge voltage and reference voltage were well within 5% of initial value. The claimed single-impulse withstand rating for the Type EVP arrester is 2.4 C.

IEEE Design Test Report Report No. EU1588-H-10.1

Type EVP Station Class Arrester

Duty Cycle



Date: 1/10/2014

EU 1588-H-10.1 2


Duty Cycle INTRODUCTION: The duty cycle testing was performed per Section 8.16 of the IEEE C62.11-2012 standard. TEST OBJECTIVE: Section 8.16.3 of the IEEE C62.11-2012 standard specifies that the 20-shot rated voltage portion be performed with 10 kA, 8/20 μs lightning impulses and the 2-shot recovery portion of the Duty Cycle test also be performed with 10 kA, 8/20 μs lightning impulses. TEST SAMPLE: As required by clause 8.16.1, prorated samples contained the minimum MOV mass per specified for the design. MCOV and rated voltages were also prorated per unit Vref to reflect the lowest margin case of the standard voltage ratings offered in this design. The test data shows the results of testing performed on three test sections. TEST PROCEDURE: The prorated test section was energized at its rated voltage and subjected to twenty 10 kA, 8/20 μs discharges spaced at 1 minute intervals. Following the twentieth impulse, the test section was placed in an oven at 68°C. After reaching 68°C, the sample was subjected to two additional 10 kA, 8/20 μs discharges. Within 5 minutes after the second high current discharge, the sample was energized at the prorated recovery voltage. Watts loss was monitored over a 30 minute period demonstrating thermal stability. TEST RESULTS: The following data summarizes the results of the duty cycle test. Figures 1 and 2 show the 1st and 20th shot performed during the rated voltage portion of the duty cycle test.

Figure 1 1st Shot @ Rated Voltage

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Figure 2

20th Shot @ Rated Voltage

Figure 3 shows the oscillogram for the 2nd 10 kA impulse applied to the section during the recovery portion of the duty cycle test.

Figure 3

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Figures 4 and 5 show the grading current through the test section at time zero and 30 minutes, demonstrating thermal recovery has occurred.

Figure 4

Recovery @ Time = 0 Minutes

Figure 5 Recovery @ Time = 30 Minutes

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Prior to and after the duty cycle test, the sample 10 kA, 8/20 μs discharge voltage is measured. Table 2 summarizes this test data.

Table 2 10 kA IR Before kVc 10 kA IR After kVc % Change in 10 kA IR

27.63 27.82 +0.7

CONCLUSION: The prorated test sample successfully completed Duty Cycle testing and demonstrated thermal stability during the recovery test. The 10 kA discharge voltage increased 0.7%, less than the allowed 10% limit specified in Section 8.16.4 of the IEEE C62.11-2012 standard. Disassembly revealed no evidence of physical damage to the test sample. The EVP arrester successfully met the Duty Cycle requirements of a Station Class arrester.

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Temporary Overvoltage



Date: 1/10/2014

EU 1588-H-11.1 2

Type EVP Station Class Surge Arrester Temporary Overvoltage

INTRODUCTION: The temporary overvoltage tests were performed per Section 8.17 of the IEEE C62.11-2012 standard. Prorated sections were used to facilitate testing of the lowest MOV mass, highest stressed arrester rating at voltages within available laboratory facility capabilities. TEST PROCEDURE: Per clause 8.17.3, each prorated sample was tested within five of the six designated time ranges a - f, spanning over-voltage durations of .01 - 10,000 seconds. Per clause 8.17.3.1, the tests were performed demonstrating TOV capability of the design under "no prior duty" conditions. For each TOV voltage setting, the test circuit applied voltage to the sample (preheated to 67.7oC) for a time duration sufficient to exceed that claimed on the "no prior duty" curve. TOV voltage was superimposed over recovery voltage such that when TOV was removed, there was no delay prior to application of recovery voltage. Recovery voltage was applied for 30 minutes to demonstrate thermal stability. Per clause 8.17.3.2 each prorated section was subjected to a “prior duty” energy discharge corresponding to class E of the switching surge energy test followed by a similar procedure of clause 8.17.3.1. TEST RESULTS: Tests were successfully completed on five EVP prorated samples in five specified time ranges. Each sample demonstrated thermal stability after TOV exposure having no signs of physical damage during inspection. Residual voltage at 10 kA measured prior to and following the complete TOV test series verified characteristics remained unchanged within acceptable limits. The following table summarizes the results of the TOV test program and applies to EVP arresters through 228 kV rating.

Table 1: Data points on Prior/No Prior Duty Curve

TOV Duration [s]

No Prior Duty TOV [p.u. MCOV]

Prior Duty TOV Class E [p.u.

MCOV] 0.02 1.527 1.483

0.1 1.485 1.433

1 1.421 1.355

10 1.36 1.279

100 1.299 1.206

1000 1.236 1.128

10000 1.175 1.054

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The following curve plots the individual data points and curves of the claimed TOV capability.

Figure 1: TOV curve for no prior and prior duty

Sample No 10KA IR Before (kVc)

10KA IR After (kVc) % Change

1 26.802 27.148 1.29% 2 26.844 27.212 1.37% 3 26.928 27.000 0.27% 4 26.844 27.105 0.97%

Table 2: 10 kA IR Before and After – Prior Duty Samples

1.45

1.365

1.302

1.106

1.510

1.467

1.401

1.259

1.05

1.1

1.15

1.2

1.25

1.3

1.35

1.4

1.45

1.5

1.55

0.01 0.1 1 10 100 1000 10000

Per U

nit o

f MC

OV

Time (sec)

EVP CLASS E ANSI PRIOR DUTY TOV CURVE @ 68°C Valid Prior Duty Test Points Valid No Prior Duty Test Points Existing Prior Duty Curve Prior Duty Curve

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Sample No 10KA IR Before (kVc)

10KA IR After (kVc) % Change

5 26.907 27.418 1.90% 6 26.781 27.283 1.87% 7 26.886 27.364 1.78% 8 26.844 27.23 1.44%

Table 3: 10 kA IR Before and After – No Prior Duty Samples Conclusion: Tests were successfully completed on four prorated samples in four specified time ranges. Each sample demonstrated thermal stability after TOV exposure. Residual voltage at 10 kA measured prior to and after the TOV test series changed much less than the allowed 10%. There was no evidence of physical damage to the test sections, validating the EVP arrester TOV capability claim.



Short Circuit Pressure Relief



Date: 1/10/2014

EU 1588-H-12.1 2

Type EVP Station Class Surge Arrester Short Circuit Pressure Relief

INTRODUCTION: The short circuit pressure relief tests were performed per Section 8.18 of the IEEE C62.11-2012 standard. The short circuit testing was performed in the Powertech High Power Laboratory in Surrey, B.C. Canada on April 1, 2011. SAMPLE PREPARATION: Samples were made in conformance to section 8.18.2.4, Design B. A 61 kV MCOV sample (longest single mechanical unit) was made for the rated current test of 63 kArms, and a 24.4 kV MCOV sample was made for the 400-800 Arms low current test. An internal fuse wire (per Note 2 of the standard) was used through the middle of both samples. This wire passed through drilled holes, 3.5 mm in size, within a half radius of the center of the internal valve elements. TEST PROCEDURE: To achieve the high levels of fault current from a limited voltage source (5.6 kV), the samples were pre-faulted with the fuse wire, as described above. The fault was initiated with the fuse wire, followed by the application of the target fault current for each arrester. TEST RESULTS: Test results are summarized in the table below.

Test Number 1 2 Arrester MCOV kVrms 61 24.4

Test Current

Actual RMS kArms 62.3 0.6 Eff. Claimable kArms 63 0.6

Peak kApeak 94.2 (Not measured) Duration ms 243 1010

Heaviest part outside circle

Soft g 864 0 Hard g 0 0

Duration of flames s 0 0

CONCLUSION: High current passed the test at a 62.3 kArms rating. Assignment of 63 kArms rating is based on recognizing that the I2t=894x106 A2s achieved (due to a longer duration of 1010 ms) is more severe than the target of I2t=794x106 A2s. Missing the exact target current is not uncommon due to the unpredictability of the arc impedance, hence the increase in arc duration to help compensate for any test mishap in not meeting the target current exactly (i.e. hedging with an ultimately more severe short circuit event). The 24.4 kV MCOV sample passed the low current short circuit test at 600 Arms for 1 second.



Maximum Design Cantilever Load (MDCL) And Moisture Ingress Test



Date: 1/10/2014

EU 1588-H-13.1 2

Type EVP Station Class Surge Arrester MDCL and Moisture Ingress Test

INTRODUCTION: The maximum design cantilever load (MDCL) and moisture ingress test were performed per Section 8.22 of the IEEE C62.11-2012 standard. SAMPLE PREPARATION: Sample was made in conformance to section 8.22.1 of the standard, using the longest EVP mechanical unit, 61 kV MCOV, in the form of a tripod base and a single bolt mount cap base (which also serves as a multi-unit joint and optional base for the purposes of this test). TEST PROCEDURE: Initial electrical tests were performed, followed by terminal preconditioning to the amount of 25 ft*lbs for a duration of 30 s. The sample was mounted in a thermal cycling oven and load was applied at 10,000 in*lbs for the tripod base and 6,667 in*lbs for the cap base in the four principal directions as outlined in the procedure, while thermally cycling in each direction following the alternating temperature extremes from the standard. At each stage of this rotation, the total deflection and residual deflection were measured. Within 24 hours of the thermal cycling the arrester was once again tested in all four principle directions for maximum deflection and residual deflection at ambient temperature. Next the arrester was subjected to the 42 hour water immersion boiling portion of the test. Within the 8 hour time frame after this test, with allowance of the sample to return to room temperature, the samples were once again electrically tested for comparison to the initial measurements. TEST RESULTS: The evaluation requirements and actual measurements are compared in the tables below and demonstrate compliance to the standard. Table #1: Electrical Comparisons – Initial vs. Final

Initial Measure (@ 22.6°C) Final Measure (@ 24.1°C) Requirement Evaluation

7.48 W @ 100% MCOV 7.68 W (+ 2.7%) < 20% increase PASS 177.4 kV, 10 kA discharge 177.1 kV (- 0.2%)* < 5% change PASS (Oscillograms of V and I) (Oscillograms) No breakdown PASS

4.1 pC PD @ 105% MCOV 3.4 pC* < 10 pC PASS *Could not complete this portion within the 8 hour timeframe due to lab constraints

EU 1588-H-13.1 3

Table #2: Deflection during thermal testing

Angle of Load Applied

[degrees]

Max Deflection at Rated Load

[mm]

Permanent Deflection at Rated Load

[mm] 0 45 2

180 46 3.5 270 43 1 90 43.5 2

Table #3: Deflection at ambient after thermal testing

Angle of Load Applied

[degrees]

Max Deflection at Rated Load

[mm]

Permanent Deflection at Rated Load

[mm] 0 43.5 1

180 46 1 270 44 0.5 90 43.5 1

CONCLUSION: The comparison of electrical values before and after the test falls within the limits of the C62.11 standard and demonstrate strong seal integrity under extreme conditions. The deflection values recorded, in combination with the electrical values measured, demonstrate that the manufacturer’s claimed mechanical requirements resulted in no permanent damage to the arrester.



Thermal Equivalency



Date: 1/10/2014

EU 1588-H-14.1 2

Type EVP Station Class Surge Arrester Thermal Equivalency

INTRODUCTION: The polymer housing accelerated aging tests were performed per Section 7.2.2.3 of the IEEE C62.11-2012 standard. PURPOSE: The purpose of this test is to verify that the thermal cooling curve for the Type EVP prorated section, when internally heated, will cool slower than that of a full size EVP arrester unit. PROCEDURE: The full size arrester and the prorated section were heated up by applying a temporary overvoltage to the test samples. The test procedure is defined in Section 7.2.2.3 of IEEE C62.11-2005 Standard. The full size arrester unit (72kV rated) was instrumented with (1) internal thermocouple located in the middle of the MOV disc stack. The temperature of the arrester thermocouple was monitored at 5 minute intervals to develop the arrester unit cooling curve. The prorated section was instrumented with a single thermocouple and its cooling rated was also monitored at 5 minute intervals. The cooling rate during the 1st 15 minutes was slower for the EVP section than the arrester. To assure thermal equivalency, as allowed by the standard, the starting temperature of the section cooling curve was raised from the targeted 140 ºC point (for the arrester) to 147.7 ºC for the prorated section. SUMMARY: The following cooling curve confirms that the cooling rate of the EVP prorated section is slower than that of the full size EVP arrester unit, confirming the thermal equivalency of the prorated section to the full size arrester.

EU 1588-H-14.1 3

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Time- Mins

Arrester Vs Prorated Section corrected cooling curve

Arrester Prorated Section

EVP Prorated Section preheated to 60+7.9 °C

ieee design test report report no. eu1588-h-00.1 · pdf fileprocedures of ieee std c62.112012,...

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